Shinobi Thieves coexist
You ever notice how Shinobi Thieves always get annihilated in UC cities? That’s because they’re strongly anti-slavery in cities where slavery is common. This attempts to fix that by setting the "Coexistence" flag on the Shinobi Thieves, so they will try a little harder to get along with the UC.
Note that I haven’t confirmed 100% whether or not this works, so far I haven’t seen any flare ups though.